Fourdrinier paper machine



May 22, 1934 J. A. 1.. BLAIS Em. 1,959,520

FOURDRINIER PAPER MACHINE Filed May 9, 1952 DBYEES Fate-inter! May rounnnmma PAPER MACHINE Joseph Achille Laurent Blais and Henry Paul Hamelin, Three Rivers, Quebec, Canada Application May 9, 1932, Serial No. 610,1'l6' In Canada March 18, 1932 4 Claims.

Our invention relates to the use of two suction rolls (1 and 1') at the inside of which are installed suction boxes (6 and '7) by means of which a partial vacuum of from to inches of mercury 5 can be obtained and used so as to be able to dry papers of all kinds.

We know that the use of perforated cylinders with one suction box already exists and has been patented to suppress the jacketed top press roll; moreover we know that this suction roll has been enlarged so as to contain two suction boxes instead of one and this was to prevent slipping of the wire over the suction roll; but our invention bears on the installation of a greater number of these suction boxes in the first suction roll (1) with its diameter increased and this arrangement eliminates most of the suction boxes that are actually placed outside of the roll and that are actually producing a considerable amount of friction 20 on the wire; we also use a second suction roll (1') under the wire and placed ahead of the suction roll (1) already described, together with a suitable suction box (2) that would be common to the two suction rolls (1 and 1') and the cover of which would be formed by a press-roll resting tangentially on the periphery of the two suction rolls (1 and 1').

The machine can also be operated without this common suction box with a displacement of suction boxes taking care of water at both nips.

In this manner the paper sheet is pressed twice, and at the same time is also compressed between the press-roll (3) and the wire, while under the influence of thevacuum.

We are aware of the existence of a Patent No. 1,701,226 where three rolls are used.

In addition we intend to place a second pressroll (4) on the forward part of the second suction roll (1') that would be used to eliminate the remaining water that can be eliminated by pressure if there may still be any in the paper after passing ahead the 1st press-roll (3), this pressroll (4) would rest partially on the suction roll (1), and the balance on a pivoted support; on a lever arm with counterpoise, or on the smoothing press (5), either of these arrangements can be made to suit the requirements of the user of the machine.

The suction box (7) shall be made movable from the position (7) to (7') so as to take the paper along the wire around roll (1') to the roll (8) at the start and on all breaks.

The diameter of roll (1) to be made from four feet for light papers or slow machine and so large as eight feet for heavy papers or fast machines, the roll (1) to vary in diameter accord.- ingly from two to fourleet, the distance between these rolls (1 and 1) to be largeron .fast machines than on slow; the roll (3) to be of any suitable material according to paper made, the roll (4) is rubber covered'and the roll (5) shall be either of granite, bronze, or any smooth material.

This invention eliminates 90% of the friction produced by the suction boxes, thereby prolongs the life of the wire, eliminates the use of the wet felts, diminishes the amount of power used, and at the same time diminishes the amount of steam used in the dryers, eliminates also all the possible breaks of the sheet before it reaches the dryers, conserves to the paper its strength with the elimination of the draws, and we claim that the porosity of the paper will also be reduced.

The two suction rolls (1 and 1') shall be run at uniform peripherical speed by means of any standard mechanism, as well as the smoothing press (5) when required.

Having described our invention what we claim -1. In a paper machine a combination of two suction rolls forming a unit with a press-roll resting tangentially on the above named suction rolls over a vacuum box common to both suction rolls; the use of a second press-roll. placed over the second suction roll partially resting on the. said suction roll and the remainder on a 35 pivot or a smoothing press.

2. In a paper machine a suction box common to the two suction rolls, with suction in a zone of each of the two rolls, and atthe same timeover the whole length of the wire 'between the two contact lines of the upper press-roll.

3. In a paper machine a combination of many suction boxes with varied and adjustable pressure at the inside of the perforated cylinders so as to: for the 1st suction roll fitted with boxes to eliminate most if not all the suction boxes breaking the wire; and also the .use of the 2nd press-roll which is tangential to the 2nd suction roll.

4. In a paper machine a combination of these 9 two press-rolls; the first tangential to the two suction rolls, and the second tangential to the second suction roll and the smoothing press.

J. A. LAURENT BLAIS. HENRY PAUL HAMELIN. 

